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Comparing AnyEvent-Fork-Remote/Remote.pm (file contents):
Revision 1.4 by root, Sun Apr 28 03:46:34 2013 UTC vs.
Revision 1.5 by root, Sun Apr 28 15:36:30 2013 UTC

… …
8 8
9 use AnyEvent; 9 use AnyEvent;
10 use AnyEvent::Fork::Remote; 10 use AnyEvent::Fork::Remote;
11 11
12 my $rpc = AnyEvent::Fork::Remote 12 my $rpc = AnyEvent::Fork::Remote
13 ->new 13 ->new_execp ("ssh", "ssh", "othermachine", "perl")
14 ->require ("MyModule") 14 ->require ("MyModule")
15 ->run ("MyModule::run", my $cv = AE::cv); 15 ->run ("MyModule::run", my $cv = AE::cv);
16 16
17 my $fh = $cv->recv; 17 my $fh = $cv->recv;
18 18
… …
43 43
44=item * C<fork> does not actually fork, but will create a new process 44=item * C<fork> does not actually fork, but will create a new process
45 45
46=back 46=back
47 47
48=head1 EXAMPLES 48=head1 EXAMPLE
49
50This example uses a local perl (because that is likely going to work
51without further setup) and the L<AnyEvent::Fork::RPC> to create simple
52worker process.
53
54First load the modules we are going to use:
55
56 use AnyEvent;
57 use AnyEvent::Fork::Remote;
58 use AnyEvent::Fork::RPC;
59
60Then create, configure and run the process:
61
62 my $rpc = AnyEvent::Fork::Remote
63 ->new_execp ("perl", "perl")
64 ->eval ('
65 sub myrun {
66 "this is process $$, and you passed <@_>"
67 }
68 ')
69 ->AnyEvent::Fork::RPC::run ("myrun");
70
71We use C<new_execp> to execute the first F<perl> found in the PATH. You'll
72have to make sure there is one for this to work. The perl does not
73actually have to be the same perl as the one running the example, and it
74doesn't need to have any modules installed.
75
76The reason we have to specif< C<perl> twice is that the first argument to
77C<new_execp> (and also C<new_exec>) is the program name or path, while
78the remaining ones are the arguments, and the first argument passed to a
79program is the program name, so it has to be specified twice.
80
81Finally, the standard example, send some numbers to the remote function,
82and print whatever it returns:
83
84 my $cv = AE::cv;
85
86 for (1..10) {
87 $cv->begin;
88 $rpc->($_, sub {
89 print "remote function returned: $_[0]\n";
90 $cv->end;
91 });
92 }
93
94 $cv->recv;
95
96Now, executing F<perl> in the PATH isn't very interesting - you could have
97done the same with L<AnyEvent::Fork>, and it might even be more efficient.
98
99The power of this module is that the F<perl> doesn't need to run on the
100local box, you could simply substitute another command, such as F<ssh
101remotebox perl>:
102
103 my $rpc = AnyEvent::Fork::Remote
104 ->new_execp ("ssh", "ssh", "remotebox", "perl")
105
106And if you want to use a specific path for ssh, use C<new_exec>:
107
108 my $rpc = AnyEvent::Fork::Remote
109 ->new_exec ("/usr/bin/ssh", "ssh", "remotebox", "perl")
110
111Of course, it doesn't really matter to this module how you construct your
112perl processes, what matters is that somehow, you give it a file handle
113connected to the new perls STDIN and STDOUT.
49 114
50=head1 PARENT PROCESS USAGE 115=head1 PARENT PROCESS USAGE
51 116
52=over 4 117=over 4
53 118
… …
59 124
60use Carp (); 125use Carp ();
61use Errno (); 126use Errno ();
62 127
63use AnyEvent (); 128use AnyEvent ();
64use AnyEvent::Util ();
65 129
66our $VERSION = 0.1; 130our $VERSION = 0.2;
67 131
68# xored together must start and and with \n 132# xored together must start and and with \n
69my $magic0 = "Pdk{6y[_zZ"; 133my $magic0 = "Pdk{6y[_zZ";
70my $magic1 = "Z^yZ7~i=oP"; 134my $magic1 = "Z^yZ7~i=oP";
71 135
… …
77 141
78Each time a new process is needed, it executes C<$path> with the given 142Each time a new process is needed, it executes C<$path> with the given
79arguments (the first array member must be the program name, as with 143arguments (the first array member must be the program name, as with
80the C<exec> function with explicit PROGRAM argument) and both C<STDIN> 144the C<exec> function with explicit PROGRAM argument) and both C<STDIN>
81and C<STDOUT> connected to a communications socket. No input must be 145and C<STDOUT> connected to a communications socket. No input must be
82consumed by the comamnd before F<perl> is started, and no output should be 146consumed by the command before F<perl> is started, and no output should be
83generated. 147generated.
84 148
85The program I<must> invoke F<perl> somehow, with STDIN and STDOUT intact, 149The program I<must> invoke F<perl> somehow, with STDIN and STDOUT intact,
86without specifying anything to execute (no script file name, no C<-e> 150without specifying anything to execute (no script file name, no C<-e>
87switch etc.). 151switch etc.).
… …
113 177
114 $proc = new_execp AnyEvent::Fork::Remote "ssh", "ssh", "otherhost", "perl"; 178 $proc = new_execp AnyEvent::Fork::Remote "ssh", "ssh", "otherhost", "perl";
115 179
116=item my $proc = new AnyEvent::Fork::Remote $create_callback 180=item my $proc = new AnyEvent::Fork::Remote $create_callback
117 181
118Basically the same as C<new_exec>, but instead of a hardcoded command 182Basically the same as C<new_exec>, but instead of a command to execute,
119path, it expects a callback which is invoked each time a process needs to 183it expects a callback which is invoked each time a process needs to be
120be created. 184created.
121 185
122The C<$create_callback> is called with another callback as argument, 186The C<$create_callback> is called with another callback as argument,
123and should call this callback with the file handle that is connected 187and should call this callback with the file handle that is connected
124to a F<perl> process. This callback can be invoked even after the 188to a F<perl> process. This callback can be invoked even after the
125C<$create_callback> returns. 189C<$create_callback> returns.
… …
286 $linecode =~ s/\s+/ /g; # takes care of \n 350 $linecode =~ s/\s+/ /g; # takes care of \n
287 $linecode =~ s/"/''/g; 351 $linecode =~ s/"/''/g;
288 substr $linecode, 70, length $linecode, "..." if length $linecode > 70; 352 substr $linecode, 70, length $linecode, "..." if length $linecode > 70;
289 353
290 $self->[1] .= '{ local @_ = ' . (aq @args) . ";\n#line 1 \"'$linecode'\"\n$perlcode;\n}\n"; 354 $self->[1] .= '{ local @_ = ' . (aq @args) . ";\n#line 1 \"'$linecode'\"\n$perlcode;\n}\n";
355
356 $self
291} 357}
292 358
293=item $proc = $proc->require ($module, ...) 359=item $proc = $proc->require ($module, ...)
294 360
295Quite the same as the same method of L<AnyEvent::Fork>. 361Quite the same as the same method of L<AnyEvent::Fork>.
… …
322=item $proc->run ($func, $cb->($fh)) 388=item $proc->run ($func, $cb->($fh))
323 389
324Very similar to the run method of L<AnyEvent::Fork>. 390Very similar to the run method of L<AnyEvent::Fork>.
325 391
326On the parent side, the API is identical, except that a C<$cb> argument of 392On the parent side, the API is identical, except that a C<$cb> argument of
327C<undef> instad of a valid file handle signals an error. 393C<undef> instead of a valid file handle signals an error.
328 394
329On the child side, the "communications socket" is in fact just C<*STDIN>, 395On the child side, the "communications socket" is in fact just C<*STDIN>,
330and typically can only be read from (this highly depends on how the 396and typically can only be read from (this highly depends on how the
331program is created - if you just run F<perl> locally, it will work for 397program is created - if you just run F<perl> locally, it will work for
332both reading and writing, but commands such as F<rsh> or F<ssh> typically 398both reading and writing, but commands such as F<rsh> or F<ssh> typically
… …
356 422
357 $self->[0](sub { 423 $self->[0](sub {
358 my $fh = shift 424 my $fh = shift
359 or die "AnyEvent::Fork::Remote: create callback failed"; 425 or die "AnyEvent::Fork::Remote: create callback failed";
360 426
361 my $code = 'BEGIN { $0 = "AnyEvent::Fork::Remote of another process"; ' . $self->[1] . "}\n" 427 my $owner = length $ENV{HOSTNAME} ? "$ENV{HOSTNAME}:$$" : "*:$$";
428
429 my $code = 'BEGIN { $0 = ' . (sq "$func of $owner") . '; ' . $self->[1] . "}\n"
362 . 'syswrite STDOUT, ' . (sq $magic0) . '^' . (sq $magic1) . ';' 430 . 'syswrite STDOUT, ' . (sq $magic0) . '^' . (sq $magic1) . ';'
363 . '{ sysread STDIN, my $dummy, 1 }' 431 . '{ sysread STDIN, my $dummy, 1 }'
364 . "\n$func*STDIN," . (aq @{ $self->[2] }) . ';' 432 . "\n$func*STDIN," . (aq @{ $self->[2] }) . ';'
365 . "\n__END__\n"; 433 . "\n__END__\n";
366
367 warn $code;#d#
368 434
369 AnyEvent::Util::fh_nonblocking $fh, 1; 435 AnyEvent::Util::fh_nonblocking $fh, 1;
370 436
371 my ($rw, $ww); 437 my ($rw, $ww);
372 438

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